Hach MP-4 User Manual

Contents

Hach MP-4 User Manual Manual pdf 34 page image

Calibration344. Push the CAL/MCLR key to enter calibration mode. The CAL, BUFFER and 7icons appear. The value displayed is for the uncalibrated sensor.Note: If a wrong buffer is added (outside of pH 6-8), 7 and BUFFER will flash and themeter does not adjust. The uncalibrated pH value that shows in step 4 assists indetermining the accuracy of the pH sensor. If the pH reading is below pH 6 or above pH 8with pH 7 buffer solution, the sensor cup needs more rinses, or the pH sensor is defectiveand needs to be replaced.5. Push UP/MS or MR/DOWN until the display reads 7.00.Note: Attempted calibration of > 1 pH point from factory calibration causes the FAC iconto appear. This means that either sensor replacement (see Section 6 on page 41) or afresh buffer solution is needed. Push the CAL/MCLR key to accept the preset factoryvalue.6. Push the CAL/MCLR key to accept the new value.The pH zero calibration is now complete. It is recommended that the user performsthe multiple point pH calibration (see section 4.10). If the user does not wish tocontinue, push any measurement key to exit.4.10 Set multiple point pH calibrationsImportant Note: Acid or base solution can be used for the second point calibrationand then use the other solution for the third point. To verify that a buffer is in thesensor cup, the display shows either the Acd icon or the bAS icon.Note: If the Acd icon or the bAS icon flash, fill the sensor cup with either an acid or basesolution to resolve the error.1. Push the CAL/MCLR key twice while in the pH measurement mode tocomplete the pH zero calibration or verify the pH 7 buffer. The CAL, BUFFERand Acd or bAS icons are displayed.2. Rinse the sensor cups three times with acid or base buffer solution.3. Fill both sensor cups again with the same solution.4. Push UP/MS or MR/DOWN until the display agrees with the buffer value.5. Push the CAL/MCLR key to accept the second point of calibration. The displayindicates the next type of buffer to be used.The two point calibration is complete now. The user can continue with the thirdpoint of the calibration or exit the calibration process. Push any measurement